The Form I-797 s an official document issued by the US citizenship and immigration service. It is the authorized approval of your stay in the United States of America. It has numerous roles. It can serve as a receipt for immigration status request. It can also serve as additional evidence of your stay in the country.
At other times, your appointment at the US Citizenship and immigration service is dictated on the form. The different versions helps the document to participate in a number of roles relating to the immigrant law enforcement. You need to verify the purpose of your particular form to ensure that you are using it correctly.